OPERATING INSTRUCTIONS AND SPECIFICATIONS NI 9234 4-Channel, ±5 V, 24-Bit Software-Selectable IEPE and AC/DC Analog Input Module Français Deutsch ni.
This document describes how to use the National Instruments 9234 and includes specifications and connector assignments for the NI 9234. Visit ni.com/info and enter rdsoftwareversion to determine which software you need for the modules you are using. For information about installing, configuring, and programming the system, refer to the system documentation. Visit ni.com/info and enter cseriesdoc for information about C Series documentation.
Safety Guidelines Operate the NI 9234 only as described in these operating instructions. This icon denotes that the component may be hot. Touching this component may result in bodily injury. Hot Surface Safety Guidelines for Hazardous Locations The NI 9234 is suitable for use in Class I, Division 2, Groups A, B, C, D, T4 hazardous locations; Class I, Zone 2, AEx nA IIC T4, and Ex nA IIC T4 hazardous locations; and nonhazardous locations only.
Substitution of components may impair suitability for Class I, Division 2. Caution For Zone 2 applications, install the system in an enclosure rated to at least IP 54 as defined by IEC 60529 and EN 60529. Caution Caution For Zone 2 applications, connected signals must be within the following limit: Capacitance .......................... 0.2 μF max Special Conditions for Hazardous Locations Use in Europe This equipment has been evaluated as Ex nA IIC T4 equipment under DEMKO Certificate No.
Special Conditions for Marine Applications Some modules are Lloyd’s Register (LR) Type Approved for marine applications. To verify Lloyd’s Register certification, visit ni.com/certification and search for the LR certificate, or look for the Lloyd’s Register mark on the module. To meet radio frequency emission requirements for marine applications, use shielded cables and install the system in a metal enclosure.
Connecting the NI 9234 The NI 9234 has four BNC connectors that provide connections to four simultaneously sampled analog input channels. AI0+ AI0– AI1+ AI1– AI2+ AI2– AI3+ AI3– Figure 1. NI 9234 Connector Assignments NI 9234 Operating Instructions and Specifications 6 ni.
Each channel has a BNC connector to which you can connect a signal source. You can also enable excitation current on a per-channel basis to connect Integrated Electronics Piezoelectric (IEPE) sensors. Refer to the NI 9234 Circuitry section for more information. The center pin of the connector, AI+, provides the DC excitation, when enabled, and the positive input signal connection. The shell of the connector, AI–, provides the excitation return path and the signal ground reference.
Refer to Figures 2 and 3 for illustrations of connecting grounded and floating signal sources to the NI 9234. Signal Source AI+ + – Common Mode Voltage NI 9234 AI– Figure 2. Connecting a Grounded Signal Source to the NI 9234 NI 9234 Operating Instructions and Specifications 8 ni.
Signal Source AI+ + – NI 9234 AI– Figure 3. Connecting a Floating Signal Source to the NI 9234 The NI 9234 can also provide an IEPE excitation current for each channel to measure ground-referenced or floating IEPE sensors. Typical IEPE sensors have a case that is electrically isolated from the IEPE electronics, so connecting the sensor to the NI 9234 results in a floating connection even though the case of the sensor is grounded. © National Instruments Corp.
NI 9234 Circuitry The NI 9234 analog input channels are referenced to chassis ground through a 50 Ω resistor. To minimize ground noise, make sure the chassis ground is connected to earth ground. Each channel is protected from overvoltages. The input signal on each channel is buffered, conditioned, and then sampled by a 24-bit Delta-Sigma ADC. You can configure each channel in software for AC or DC coupling. For channels set to AC coupling, you can turn the IEPE excitation current on or off.
2 mA IEPE on/off AC/DC Coupling AI+ + ADC AI– Current Limiting Diodes 50 Ω – Common Mode Bias Current Amplifier and Prefilter NI 9234 Figure 4. NI 9234 Input Circuitry for One Channel The NI 9234 uses common-mode bias current to bias the current-limiting diodes when IEPE current is turned off. When the NI 9234 is using grounded signal sources, this current causes an error that is dependent on the AI– lead impedance.
Signal Source AI+ + – AI– Lead Impedance AI– Common Mode Bias Current NI 9234 Figure 5. Measurement Error Introduced by Common-Mode Bias Current The NI 9234 also has TEDS circuitry. For more information about TEDS, go to ni.com/info and enter rdteds. NI 9234 Operating Instructions and Specifications 12 ni.
Understanding NI 9234 Filtering The NI 9234 uses a combination of analog and digital filtering to provide an accurate representation of in-band signals while rejecting out-of-band signals. The filters discriminate between signals based on the frequency range, or bandwidth, of the signal. The three important bandwidths to consider are the passband, the stopband, and the alias-free bandwidth.
0.025 Gain (dB) 0.000 –0.025 –0.050 0 0.1 0.2 0.3 0.4 0.5 Frequency/Data Rate Figure 6. NI 9234 Typical Passband Flatness NI 9234 Operating Instructions and Specifications 14 ni.
Stopband The filter significantly attenuates all signals above the stopband frequency. The primary goal of the filter is to prevent aliasing. Therefore, the stopband frequency scales precisely with the data rate. The stopband rejection is the minimum amount of attenuation applied by the filter to all signals with frequencies within the stopband. Alias-Free Bandwidth Any signal that appears in the alias-free bandwidth of the NI 9234 is not an aliased artifact of signals at a higher frequency.
Understanding NI 9234 Data Rates The frequency of a master timebase (fM) controls the data rate (fs) of the NI 9234. The NI 9234 includes an internal master timebase with a frequency of 13.1072 MHz, but the module also can accept an external master timebase or export its own master timebase. To synchronize the data rate of an NI 9234 with other modules that use master timebases to control sampling, all of the modules must share a single master timebase source.
of 13.1072 MHz, the result is data rates of 51.2 kS/s, 25.6 kS/s, 17.067 kS/s, and so on down to 1.652 kS/s, depending on the value of n. When using an external timebase with a frequency other than 13.1072 MHz, the NI 9234 has a different set of data rates. Note The cRIO-9151 R Series Expansion chassis does not support sharing timebases between modules. Sleep Mode This module supports a low-power sleep mode. Support for sleep mode at the system level depends on the chassis that the module is plugged into.
Specifications The following specifications are typical for the range –40 to 70 °C unless otherwise noted. Input Characteristics Number of channels.......................... 4 analog input channels ADC resolution................................. 24 bits Type of ADC..................................... Delta-Sigma (with analog prefiltering) Sampling mode ................................. Simultaneous Type of TEDS supported .................. IEEE 1451.4 TEDS Class I Internal master timebase (fM) Frequency .
Data rate range (fs) using external master timebase Minimum.................................... 0.391 kS/s Maximum ................................... 52.734 kS/s f M ÷ 256 Data rates1 (fs) ................................... --------------------- , n = 1, 2, …, 31 n Input coupling................................... AC/DC (software-selectable) AC cutoff frequency –3 dB .......................................... 0.5 Hz –0.1 dB....................................... 4.
AC cutoff frequency response 0.5 Gain (dB) 0.0 –0.5 –1.0 0 1 2 4 3 5 6 7 8 9 10 Frequency (Hz) NI 9234 Operating Instructions and Specifications 20 ni.
Input range ........................................ ±5 V AC voltage full-scale range Minimum.................................... ±5 Vpk Typical ........................................ ±5.1 Vpk Maximum ................................... ±5.2 Vpk Common-mode voltage range (AI– to earth ground) ........................ ±2 V max IEPE excitation current (software-selectable on/off) Minimum.................................... 2.0 mA Typical ........................................ 2.1 mA Power-on glitch.......
IEPE compliance voltage.................. 19 V max If you are using an IEPE sensor, use the following equation to make sure your configuration meets the IEPE compliance voltage range. (Vcommon-mode + Vbias ± Vfull-scale) must be 0 to 19 where Vcommon-mode is the common-mode voltage applied to the NI 9234 Vbias is the bias voltage of the IEPE sensor Vfull-scale is the full-scale voltage of the IEPE sensor Overvoltage protection (with respect to chassis ground) For a signal source connected to AI+ and AI– .
Accuracy1 Percent of Reading (Gain Error) Percent of Range* (Offset Error) Calibrated max (–40 to 70 °C) 0.34%, ±0.03 dB ±0.14%, 7.1 mV Calibrated typ (25 °C ±5 °C) 0.05%, ±0.005 dB ±0.006%, 0.3 mV Uncalibrated max (–40 to 70 °C) 1.9%, ±0.16 dB ±0.27%, 13.9 mV Uncalibrated typ (25 °C ±5 °C) 0.48%, ±0.04 dB ±0.04%, 2.3 mV Measurement Conditions * 1 Range = 5.1 Vpk Refer to the NI 9234 Circuitry section for information regarding grounded signal sources and measurement accuracy.
Gain drift Typical ........................................ 0.14 mdB/°C (16 ppm/°C) Maximum ................................... 0.45 mdB/°C (52 ppm/°C) Offset drift Typical ........................................ 19.2 μV/°C Maximum ................................... 118 μV/°C Channel-to-channel matching Gain Typical.................................. 0.01 dB Maximum............................. 0.04 dB Phase ( fin in kHz) ....................... fin · 0.045° + 0.04 max Passband Frequency ..................
Alias-free bandwidth ........................ 0.45 · fs Oversample rate ................................ 64 · fs Crosstalk (1 kHz).............................. –110 dB CMRR (fin ≤ 1 kHz) Minimum.................................... 40 dB Typical ........................................ 47 dB SFDR (fin = 1 kHz, –60 dBFS) ......... 120 dB Idle channel noise and noise density Idle Channel Noise Noise density 51.2 kS/s 25.6 kS/s 2.
Total harmonic distortion (THD) Input Amplitude 1 kHz 8 kHz –1 dBFS –95 dB –87 dB –20 dBFS –95 dB –80 dB Intermodulation distortion (–1 dBFS) DIN 250 Hz/8 kHz 4:1 amplitude ratio ..................... –80 dB CCIF 11 kHz/12 kHz 1:1 amplitude ratio ..................... –93 dB MTBF ...............................................
Power Requirements Power consumption from chassis Active mode ............................... 900 mW max Sleep mode ................................. 25 μW max Thermal dissipation (at 70 °C) Active mode ............................... 930 mW max Sleep mode ................................. 25 μW max Physical Characteristics If you need to clean the module, wipe it with a dry towel. Weight............................................... 173 g (6.1 oz) © National Instruments Corp.
Safety Safety Voltages Connect only voltages that are within the following limits. Channel-to-earth ground................... ±30 V max, Measurement Category I Isolation Channel-to-channel .................... None Channel-to-earth ground ............ None Measurement Category I is for measurements performed on circuits not directly connected to the electrical distribution system referred to as MAINS voltage. MAINS is a hazardous live electrical supply system that powers equipment.
Hazardous Locations U.S. (UL) .......................................... Class I, Division 2, Groups A, B, C, D, T4; Class I, Zone 2, AEx nA IIC T4 Canada (C-UL) ................................. Class I, Division 2, Groups A, B, C, D, T4; Class I, Zone 2, Ex nA IIC T4 Europe (DEMKO).............................
Electromagnetic Compatibility This product meets the requirements of the following EMC standards for electrical equipment for measurement, control, and laboratory use: • EN 61326 (IEC 61326): Class A emissions; Basic immunity • EN 55011 (CISPR 11): Group 1, Class A emissions • AS/NZS CISPR 11: Group 1, Class A emissions • FCC 47 CFR Part 15B: Class A emissions • ICES-001: Class A emissions Note For the standards applied to assess the EMC of this product, refer to the Online Product Certification se
CE Compliance This product meets the essential requirements of applicable European Directives as follows: • 2006/95/EC; Low-Voltage Directive (safety) • 2004/108/EC; Electromagnetic Compatibility Directive (EMC) Online Product Certification Refer to the product Declaration of Conformity (DoC) for additional regulatory compliance information. To obtain product certifications and the DoC for this product, visit ni.
Shock and Vibration To meet these specifications, you must panel mount the system. Operating vibration Random (IEC 60068-2-64)......... 5 grms, 10 to 500 Hz Sinusoidal (IEC 60068-2-6) ....... 5 g, 10 to 500 Hz Operating shock (IEC 60068-2-27).............................. 30 g, 11 ms half sine, 50 g, 3 ms half sine, 18 shocks at 6 orientations Environmental National Instruments C Series modules are intended for indoor use only but may be used outdoors if installed in a suitable enclosure.
Operating humidity (IEC 60068-2-56).............................. 10 to 90% RH, noncondensing Storage humidity (IEC 60068-2-56).............................. 5 to 95% RH, noncondensing Maximum altitude............................. 2,000 m Pollution Degree (IEC 60664) .......... 2 Environmental Management NI is committed to designing and manufacturing products in an environmentally responsible manner.
Waste Electrical and Electronic Equipment (WEEE) EU Customers At the end of their life cycle, all products must be sent to a WEEE recycling center. For more information about WEEE recycling centers and National Instruments WEEE initiatives, visit ni.com/ environment/weee.htm. ⬉ᄤֵᙃѻક∵ᶧࠊㅵ⧚ࡲ⊩ ˄Ё RoHS˅ Ёᅶ᠋ National Instruments ヺড়Ё⬉ᄤֵᙃ ѻકЁ䰤ࠊՓ⫼ᶤѯ᳝ᆇ⠽䋼ᣛҸ (RoHS)DŽ݇Ѣ National Instruments Ё RoHS ড়㾘ᗻֵᙃˈ䇋ⱏᔩ ni.com/environment/rohs_chinaDŽ (For information about China RoHS compliance, go to ni.
Where to Go for Support The National Instruments Web site is your complete resource for technical support. At ni.com/support you have access to everything from troubleshooting and application development self-help resources to email and phone assistance from NI Application Engineers. National Instruments corporate headquarters is located at 11500 North Mopac Expressway, Austin, Texas, 78759-3504. National Instruments also has offices located around the world to help address your support needs.
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